1. Field of the Invention
This invention relates to fish bait, and more particularly the preservation of Ceratomia catalpae (order Lepidoptera, Family Sphingidae) sometimes referred to as “Catalpa or Catawba worm” larvae through the cleansing, blanching, and freezing of the larvae in individual bags and successively larger bags. This finished frozen fish bait does not contain any chemical preservatives, and can be kept frozen with limited deterioration for months.
2. Description of the Prior Art
Information on the Ceratomia catalpae, commonly referred to as the Catalpa or Catawaba worm can be found in the following publications.    Coder, Kim D. Professor, The University of Georgia. December 1999. “Southern Catalpa: The Fish Bait Tree”. Retrieved on Jul. 8, 2003 from: http://www.forestry.uga.edu/warnell/service/library/index.php3?docID=178&docHistory[ ]=2    Baerg, W. J. 1935. “Three shade tree insects, II Great Elm Leaf Beetle, Catalpa Sphinx, and Eastern Tent Caterpillar”. University of Arkansas Agricultural Experiment Station Bulletin No. 317. 28 pages.    Howard L. O., Chittenden, F. H., 1916. “The Catalpa Sphinx”. United States Department of Agriculture Farmers Bulletin. Bulletin 705, Feb. 16, 1916.    Hyche, L. L. 1994. “The Catalpa Sphinx”. Alabama Agricultural Experiment Station, Auburn University Alabama. Leaflet 106. March 1994    Nayar J. K., Fraenkel G. 1963. “The Chemical Basis of the Host Selection in the Catalpa Sphinx, Ceratomia catalpae (Lepidoptera, Sphingidae). Annals of the Entomological Society of America. Vol 5. pages 119-122.
Catawba or Catalpa caterpillars are notoriously prized fishing bait, used for catching most species of freshwater fish in the United States. The caterpillars are highly regarded by fishermen, and references to their harvesting for fishing bait has been recorded back to the 1870's.
Catawba or Catalpa caterpillars are the larval stage of the Catalpa Sphinx moth (Ceratomia catalpae, Order Lepidoptera, Family Sphingidae) and sometimes referred by fishermen as “Catawba worms” or “Catalpa worms”. The catalpa sphinx moth is found in much of the Eastern US from Florida to New York, west to Michigan, Iowa, and Kansas and Texas. The larvae is a monophagous insect that feed exclusively on the leaves of the deciduous Catalpa speciosa, Catalpa bignonioides, Catalpa ovata (also known as Catalpa kaempferi) and Catalpa bungei trees. Catalpa trees may be defoliated completely by the Catalpa caterpillars and kept bare the entire growing season so that the trees are badly damaged or even killed. Thus, loss of foliage by the larvae is especial serious concern for shade and ornamental trees as well as nursery stock.
The Catalpa Sphinx moth has four distinct life stages: adult, pupa, larva, and egg. The adult stage is a large, gray, nocturnal moth with a wing span of approximately 65-70 mm when extended. After mating the moths, lay between 1-1000 small, whitish, greenish eggs on the underside of Catalpa tree leaves. The eggs hatch into larva, and begin to “skeletonize” the Catalpa trees. The larval stage is the longest stage (approximately 16 days) in which the caterpillars molt 4-5 times, and as they continue to eat the Catalpa foliage and grow. Full grown larva are approximately 3-4 inches long, and marked with a black band with a white line running along the side of the band, and a distinctive “horn” on their backs. The sides of the larvae are usually pale yellow. However, there are various colors and shades that have been noted in Catalpa larvae. The approximate time frame for the adult, egg, and larval stages is 21-25 days. The final stage of the Catalpa Sphinx Moth is the pupation stage. After the larvae have become adults (approximately 3-4 inches long), they fall or drop from the Catalpa tree and enter the soil. After entering the soil, they begin the pupation stage. The pupa is usually reddish in color, and about 30-40 mm long. Excluding winter moths, the pupas usually reemerge with two weeks as moths. The entire life cycle of the Catalpa Sphinx Moth, from pupa to pupa is approximately 30-40 days depending on environmental factors, and climate.
In addition to the complexity of maintaining a plantation of Catalpa trees sufficient to provide the exclusive foliage for the Catalpa larvae to eat and the complex life cycle of the moth, commercially rearing the Catalpa caterpillars also has another barrier, natural predators. The Catalpa larvae are attacked by parasites and by a small wasp. The wasp, Apanteles congregatus is a small winged, wasp-like insect that stings and lays its eggs in the Catalpa larvae. The larvae develops and feeds on the caterpillar, and when ready for transformation (back into a wasp) eats a hole through the skin of the caterpillar and spins a white cocoon on the outside of the “Catalpa worms”. Once stung, Catalpa larvae are commercially useless (for fishing bait) and dies before adulthood. Another predator of the “Catawba worm” are the Tachina Flies, which commonly attack the larvae. In one reported example of a Catalpa worm egg mass that originally contained 807 eggs, due to parasitism only 4 caterpillars survived. It has also been our experience that the pupae stage of the “Catawba worm” is also vulnerable to predation. Once the larvae begin pupation in the soil, they are susceptible to raccoons, skunks and other animals looking for food and are “dug out” of the soil and eaten. It has also been our experience that common Toads and Frogs eat smaller Catalpa larvae during the night, if they happen to fall off the trees, and that other insects such as the common yellow jacket and all species of ants found in the Catawba County, N.C. region actively pursue and kill the young larvae.
Once the aforementioned factors have been overcome, and a supply of “Catawba worms” is readily available, getting the product to the end consumer remains a major problem. Harvesting Catawba worms is difficult at best. It has been our experience, that most fishermen prefer the adult larvae as fishing bait. Thus, the majority of the caterpillars harvested are approximately 3-4 inches long, and approximately ½ wide. Since the larva exclusively eats the leaves of specific species of Catalpa trees, the larvae must be picked from the trees. This has to be done with minimal handling to the caterpillars as possible as, if the larva is dropped or agitated they “spit” at their aggressor loosing part of their digested leaves, which leads to deterioration in the quality of the larva (to fishermen). Also, if disturbed the larva has a tendency to “defensively” squirm or swing their heads to fend off what is attacking them. If this happens once the larvae is harvest and placed in the bucket, they can damage other worms in the same bucket. This in turn, makes them less appealing to the end consumer, the fisherman.
Once the Catawba worms are harvested they have to be delivered to the retail outlets. It has been our experience that live Catawba worms only last 5-10 days once they have been harvested, packaged and refrigerated. After approximately 10 days or less in the refrigerator, the live caterpillars or worms become generally worthless to fisherman. The Catawba worms turn yellow-blackish, dry out, develop mold and become excessively tainted with frass from other worms surrounding them. Thus, to most Bait and Tackle stores who sell fish bait, the shelf life of live Catawba worms would only be approximately 5-7 days. FIG. 13 is a color photograph of live Catalpa or Catawba worms that have been refrigerated for 10 days. Comparison with the color photograph of FIG. 11 shows the deterioration of the live Catalpa or Catawba worms during this period.
Therein lies the problem, how can a Catawba worm be supplied to fishermen when the crop is seasonal, when it grows exclusively on certain species of trees, that are susceptible to parasites, difficult to harvest and rear, and only has a “fishable” shelf life in the refrigerator of 5-10 days. Traditional methods of preserving Catawba worms to make them available year round were to place the caterpillars in sawdust, cornmeal, flour, and pint jars of water and then freezing them. My first preserved bait was a Catalpa worm frozen in Corn Meal. However, the shelf life of these baits was only a few weeks. After that, the caterpillars turned yellow-blackish, suffered from freezer burn, and when thawed out became brittle (skin) and soggy. FIG. 12 shows an example of Catalpa or Catawba worms frozen by this prior art method. To most fishermen, this product was unacceptable. My next step was to try food grade preservatives, rubbing alcohol, and other common preservatives used in fish bait. However, I have found the natural colorations, scent, and texture of the bait to be less fishable and attractive to both the consumers and the targeted fish (through fishing with the worms). Also, that some common preservatives used in fishing bait were really not what you wanted to ingest yourself or feed to your family, if you used a typically preserved bait to catch a fish, and in turn ate that fish.
U.S. Pat. No. 5,776,523 entitled “Method for preserving baits”, discloses an example of a method of preserving fish bait by immersing the bait in a solution of formalin to prevent decay by bacterial action, then rinsing the bait with running water, and placing the bait in a container of a second aqueous solution of grain alcohol. According to the Occupational Safety and Health Administration (OSHA), the term “formalin” is the aqueous solution, particularly those containing 37-50% formaldehyde and a 6 to 15% alcohol stabilizer (OSHA Fact Sheet on Formaldehyde). It is also noted in that fact sheet that “Formaldehyde” is a “suspected human carcinogenic that is linked to nasal cancer and lung cancer”. In addition, in the publication “Medical Management Guidelines for Formaldehyde” published by the Agency for Toxic Substances and Disease Registry (an agency of the Department of Health and Human Services) states that “Ingestion of aqueous solutions of formaldehyde can result in severe corrosive injury to the esophagus and stomach” and that “formaldehyde may reasonably anticipated to be a carcinogen”.
As realized in other means of preserving fish bait in prior art, successfully preserving products for a long period of time was difficult and certain chemical preservatives were usually added to maintain the shelf life of the product. Also, that preservation of Catalpa worms had generally not been documented. For example, U.S. Pat. No. 4,161,158 entitled “Preservation of Live Fish Bait” a method of preserving live underground and surface dwelling fishing bait is shown. This method involves sterilizing the fish bait in a solution of 10-15% (by weight) ethanol for 10-15 seconds, packing the bait in a media containing nutrients, an antibiotic (penicillin) then a stress relief (cortisone), and finally keeping at a temperature between 34-55 degrees Fahrenheit.
In U.S. Pat. No. 4,503,077 entitled “Method for Preserving Fishing Bait” there is disclosed a method for preserving bait by cleaning the bait, pre-cooling the organisms, freezing the bait, condensing, evacuating and heating the bait to remove water, and then separating and packaging the bait.
In U.S. Pat. No. 4,160,847 entitled “Process of Improving the Freeze-Thaw Stability of Fish Bait”, the method to improve freeze-thaw stability of fish bait by impregnating fish such as herring in a vacuum with a water soluble, non-toxic glycol then draining and freezing the bait.
Although not directly concerned with the problem of preserving fishing baits, U.S. Pat. No. 6,020,013 entitled “Method of preventing freezer burn on food in storage bags”, discloses a method of preventing freezer burn on frozen foods by providing a triple seal to prevent the ingress of ambient air through the seals into the interior of the storage bags.